RELATION OF VEGETABLE ALKALIES. 177 



matter, their action on the healthy as well as the dis- 

 eased organism admits of a surprisingly simple explana- 

 tion. If we are not tempted to deny, that the chief 

 constituent of soup may be applied to a purpose corre- 

 sponding to its composition in the human body, or that 

 the organic constituent of bones may be so employed in 

 the body of the dog, although that substance (gelatine in 

 both cases) is absolutely incapable of yielding blood ; if, 

 therefore, nitrogenized compounds, totally different from 

 the compounds of proteine, may be employed for pur- 

 poses corresponding to their composition ; we may 

 thence conclude that a product of vegetable life, also 

 different from proteine, but similar to a constituent of 

 the animal body, may be employed by the organism in 

 the same way and for the same purpose as the natural 

 product, originally formed by the vital energy of the 

 animal organs, and that, indeed, from a vegetable sub- 

 stance. 



The time is not long gone by, when we had not the 

 very slightest conception of the cause of the various 

 effects of opium, and when the action of cinchona bark 

 was shrouded in incomprehensible obscurity. Now 

 that we know that these effects are caused by crystalli- 

 zable compounds, which differ as much in composition 

 as in their action on the system ; now that we know the 

 substances to which the medicinal or poisonous energy 

 must be ascribed, it would argue only want of sense to 

 consider the action of these substances inexplicable ; 

 and to do so, as many have done, because they act in 



